#公用的自定义工具类
from flask import session, current_app, g

from info.models import User
import functools

def do_index_class(index):
    """ 返回指定索引对应的类名"""

    if index == 0:
        return 'first'
    elif index == 1:
        return 'second'
    elif index == 2:
        return 'third'

    return ''

def user_login_data(f):

    #解决两个不同路由对应同一个视图函数，会报错
    #使用functools。wraps去装饰内层函数，可以保持当前装饰器去装饰的函数的__name__的值不变
    @functools.wraps(f)
    def wrapper(*args,**kwargs):

        user_id = session.get ('user_id', None)
        user = None
        if user_id:
            try:
                user = User.query.get (user_id)
            except Exception as e:
                current_app.logger.error (e)
        g.user = user
        return f(*args,**kwargs)

    return wrapper

# def query_user_data():
#     user_id = session.get ('user_id', None)
#     user = None
#     if user_id:
#         try:
#             user = User.query.get (user_id)
#         except Exception as e:
#             current_app.logger.error (e)
#         return user
#     return None